cbor_validate: Validate CBOR

In zucbor: Deterministic and Secure CBOR Encoding and Decoding

Validate CBOR

Description

Checks that x holds well-formed, valid CBOR within the given limits, without building any R value. This is exactly the check cbor_decode() runs before it builds anything, so the two agree about the bytes; they disagree only where the bytes are valid but R cannot hold the value, such as a text string containing U+0000.

Usage

cbor_validate(
  x,
  sequence = FALSE,
  deterministic = FALSE,
  duplicate_keys = FALSE,
  max_depth = 256L,
  max_size = 64 * 1024^2,
  max_items = 1e+06,
  error = FALSE
)

Arguments

x	A raw vector.
sequence	If TRUE, x is an RFC 8742 CBOR sequence of zero or more items; if FALSE, it must be exactly one item.
deterministic	If TRUE, also require RFC 8949 section 4.2.1 core deterministic encoding: shortest integers, lengths and floats, definite lengths, map keys in bytewise order, and bignums in preferred form.
duplicate_keys	If FALSE (the default), a map with the same key twice is invalid.
max_depth	Deepest nesting allowed, counting arrays, maps and tags. At most zucbor_info()$max_depth_cap.
max_size	Largest input allowed, in bytes, or Inf.
max_items	Most data items allowed, counting every tag and every chunk of an indefinite-length string, or Inf.
error	If TRUE, raise the classed condition describing the fault instead of returning FALSE; see zucbor-conditions.

Details

The check covers well-formedness (RFC 8949 section 3), UTF-8 in text strings, the content of the tags RFC 8949, RFC 8943 and RFC 8746 restrict (their content type, the date text of tags 0 and 1004, the length of a typed array, the shape of a multi-dimensional array), duplicate map keys (compared by value, so 1 encoded in one byte and in two is the same key), and the limits.

Value

TRUE or FALSE; with error = TRUE, TRUE invisibly or an error.

Examples

cbor_validate(as.raw(c(0x83, 0x01, 0x02, 0x03)))   # [1, 2, 3]
cbor_validate(as.raw(c(0x83, 0x01, 0x02)))         # truncated
cbor_validate(as.raw(c(0xa2, 0x01, 0x00, 0x01, 0x00)))  # {1: 0, 1: 0}
cbor_validate(as.raw(c(0x01, 0x02)), sequence = TRUE)

zucbor documentation built on Oct. 21, 2026, 5:14 p.m.